End of page indicator for typewriters



NOV- 2, 1.954 J. J. DAvrrT, JR

END OF PAGE INDICATOR l'FOR TYPEWRITERS.

4Filed June 11, 1951 INVENToR. Jy/f'f?.

M IW

United States l Patent F PAGE INDICATOR FOR James J. Davitt, Jr., Roselle, N. J., assignor to Mary Martha Davitt, Roselle, N. J.

Application June 11, 1951, Serial No. 230,987

3 Claims. (Cl. 197-189) This invention relates to improvements in end-of-page alarms or indicators for typewriters.

It is a feature of this invention to provide an alarm device which may be adjusted to adapt itself for use with sheets of different lengths such as half lengths, letter size, legal size and document size.

Another object of this invention is to provide an inexpensive, rugged, indicating means which may readily be adapted as an accessory to standard typewriters. The typist on the machine without any alarm device must constantly guard against typing too many lines on a page. This task is at times overlooked since the typist becomes engrossed in the transcription and also because the end of the page is concealed behind the typewriter laten. p A need, therefore, has existed for some type of alarm means which will automatically apprise the typist of the approach of the end of the page.

My device is attached to the carriage without substantial modification thereof and is operated by rotation of the typewriter platen, to actuate a signal when the platen has moved a sheet to the point where it leaves the desired margin below the typing. To this end I have designed a gear mechanism which connects the platen and a clapper which in turn strikes a modified platen knob acting as a bell to apprise the typist of the end of the page.

Other advantages of my invention will be apparent in the course of the ensuing description taken from the accompanying drawings in which Figure l is a perspective view of my device in relation to a typewriter;

Figure 2 is a top View of my device;

Figure 3 is a view taken on lines 3-3 of Figure 2;

Figure 4 is a partial view similar to Figure 3 illustrating the relationship of parts prior to release of the clapper, and

Figure 5 is an enlarged view similar to Figure 4.

Referring specifically to the drawings, it is `to be noted that my alarm device essentially comprises two componente; the lirst component being a gear and bell combination designated 1, and the other component being the clapper support and indicating mechanism generally designated 2.

The gear and bell combination 1 is substituted for the platen knob found on the usual typewriter, and is of the same size and readily adapted for substitution of the same. This substitution is performed as follows:

The usual platen knob is backed off the platen shaft 3 and the new gear and bell combination 1 comprising gear 4 on shaft 5 and combined bell and knob 6 on the end of the shaft is screwed in place thereof. The bell and knob 6 is formed from a metallic material which when struck will emit a bell-like tone. Member 6 is serrated on its outer periphery. The gear and indicating member 2 is fastened onto the carriage by means of supporting screw 7- which extends through gear 8, supporting collars 9 and 10 and into threading engagement with the carriage sidewall 11. Supporting screw 7 has a raised portion 12 formed near the head thereof so that the portion 12 only bears against the collar 9 so that the gear 8 is freely rotatable on raised portion 12 of the screw.

An indicating and clapper supporting member generally indicated at 13 surrounds screw 7 and is held between collars 9 and 10 in such relation therewith that it does not rotate about the axis of screw 7.

Patented Nov. 2, 1954 This member 13 comprises two elements: an indicating arm 14 and a clapper supporting arm 15. The indicating arm 14 extends upwardly so that the typist is able to see the pointer at the end of the arm 14 whenever he is in the usual typing position. Clapper supporting member 15 extends generally rearwardly from the Vscrew 7 and pivotally supports at its outer end clapper 16. The clapper member 16 is substantially V-shaped and is pivoted at one end 17 to its supporting member 16. The opposite end 18a extends at substantially right angles to its supporting member 18 projecting under the bell 6 to be in striking relation therewith. At the eX- lmember 16, and serves to bias the clapper 19 into striking relationship to the bell and knob 6. Substantially at the vertex of clapper member 16 an inwardly projecting pin 21 is positioned and is adapted to be engaged by the cam member 22 pivoted at 22a to gear 8. A cam restraining pin 23 projects inwardly from gear S and is adapted to restrain movement of cam 22 about its pivot 22a in certain instances.

On the inner side of gear 8 are several projecting tabs bearing indicia D, L, W and H. These tabs indicate the different sizes of pages which may be used in connection with this mechanism, i. e. D indicates document size, L, legal size, W, whole size and H, half size.

Figures 3, 4 and 5 illustrate the various positions of the cam and clapper member, the activation of which is as follows: As the gear 8 in mesh with gear 4 is rotated clockwise (Fig. 3) by rotation of the platen, the cam member 22 moves toward engagement with projecting pin 21 of member 16.

As illustrated in Figure 4 the projecting pin 21 has been engaged by cam 22 which is prevented from freely rotating about its pivot 22a by engagement with cam restraining pin 23. This causes the projecting pin 21 to move downwardly along the left face of cam 22, biasing spring 20 until projecting pin 21 overrides the peak of cam 22, at which time the clapper member 16 moves upwardly with suflicient force under action of spring 20 to cause clapper 19 to strike bell 6 warning the typist that the end of page has been reached.

In operation the typist rotates platen knob and bell 6 until the indicating indicium denoting the size of paper he is using appears under the pointer of indicating arm 14. At this point the typist inserts the paper at `the back of the platen and rotates the platen until the paper is in the desired typing position. As paper is fed through the machine under action of the platen rotation, the gear 4 turns gear 8 causing the cam 22 to approach and engage projecting pin 21. When this occurs, the actuation of the alarm will take place in the manner heretofore described.

It is to be noted that upon reverse rotation of gear 8, which takes place for instance whenever the typist Wishes to back the paper out from the platen, projecting pin 21 is engaged by the right side of the cam 22 (Fig. 3) and the cam rotates freely about its supporting pin 22a without biasing spring 20.

Since the indicator is set prior to insertion of the paper in the typewriter, it is readily observed that the indicator and alarm are independent of the place at which typewriting is initiated on the paper. The typist, therefore, after initial setting, merely types until a bell warns of the end of the page.

While the invention has been illustrated and described in a preferred form, it is to be understood that it is not limited to the form shown herein but may be illustrated in other forms which come within the scope of the appended claims.

I claim:

l. In a typewriter having a carriage and a platen shaft, an attachment including a combined bell and knob mounted on the end of the platen shaft, a first gear mounted on the platen shaft inwardly of said combined bell and knob, a second gear rotatably mounted on the typewriter carriage and meshing with said first gear, biased clapper means pivotally mounted on said carriage, a clapper mounted on said clapper means adapted to strike the inner periphery gear, a stationary pointer mounted on said carriage in.

indicating relationship with said indicia on said second gear, biased clapper means pivotally mounted on. said carriage, a clapper mounted on said clapper meansA adapted to strike the inner periphery of said bell, and cam means on said second gear adapted to engage said clapper means to cause said clapper to ring said bell.

3. In a typewriter having a carriage and a platen shaft, an attachment including a first gear and bell combination mounted on the platen shaft for rotation therewith, a second gear rotatably mounted on the typewriter carriage having indicia thereon and meshing with saidv first gear, a stationary pointer mounted on said carriage in indicating relationship with said indicia on. said secondI gear, a clapper arm supportng. member mounted. on said carriage, a clapper arm pivotally mounted on said clapper arm supporting member at one end and having a clapper at the opposite end adapted to engage said bell, a spring supported from said carriage at one end and attached to said clapper arm at the opposite end, a pivotal cam member on said second gear, a cam restraining pin on said second gear adapted to limit pivotal movement of said cam member in one direction, and a projecting pin on said clapper arm adapted to be engaged by said cam member to cause tensioning of said spring and after sufcient rotation of said cam member with said second gear to release the clapper arm causing said clapper to strike said bell.

References Cited in the le of this patent UNITED STATES PATENTS 

